we know that
The simple interest formula is equal to
where
A is total amount that must be paid
P is the total amount of money borrowed
I is the amount of interest
r is the rate of interest
t is Number of Time Periods
in this problem we have
P=$11,000
r=9%=9/100=0.09
t=60/365 years
substitute
so
Part a) The interest is
I=11,162.74-11,000
I=$162.74
Part b) the total amount is
A=$11,162.74